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Topic Title: SWEATY BOLLARDS
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Created On: 05 July 2014 09:07 AM
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 05 July 2014 09:07 AM
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I have been assisting in the installation of low footpath LED lighting bollards. They each are rated at 100mA 230 Volt AC and are about 1.5 metres high. The posts have been sunk into the ground and the bases concreted for stability. The cable is three core 6.0mm2 SWA. The person running the job is connecting the SWAs to a metal clad switched fused connection unit fused at 3 Amps. The bollard head is connect via flex within the post. The bollard posts are about the size that you can get your fist into comfortably 200mm dia. approx.). The problem is that as the job has been proceeding I have noticed that overnight condensation builds up inside the bollard post and wets the circuit board that is situated within the post directly below the head. There is no means of ventilation provided by the manufacturers so condensation has nowhere to go during the day. What is your opinion of this, and has anyone ever come across it before? Is there a solution please?
 05 July 2014 09:30 AM
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phantom9

Posts: 668
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That's a horrible topic heading. Yeuch!

Maybe this question should be directed at the bollard manufacturers. I can't see how this can be an installers problem unless the manufacturer's installation instructions have not been followed.
 05 July 2014 09:40 AM
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rocknroll

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The two 600mm ones I bought a few months ago for my own use, decking steps, had a silica crystal pack inside to alleviate condensation, its purpose being to keep the glass clear and obviously protect the electronics from the said condensation, you can buy the silica packs in a bag and they come in different weights usually in grams.

Or have you thrown away the ones that came with the unit as most people do. LOL

regards

-------------------------
"Take nothing but a picture,
leave nothing but footprints!"
-------------------------
"Oh! The drama of it all."
-------------------------
"You can throw all the philosophy you like at the problem, but at the end of the day it's just basic electrical theory!"
-------------------------
 05 July 2014 09:55 AM
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Originally posted by: rocknroll

The two 600mm ones I bought a few months ago for my own use, decking steps, had a silica crystal pack inside to alleviate condensation, its purpose being to keep the glass clear and obviously protect the electronics from the said condensation, you can buy the silica packs in a bag and they come in different weights usually in grams.



Or have you thrown away the ones that came with the unit as most people do. LOL



regards



Hello rocknroll,
thanks for your comments. The use of silica gel packs will not solve the problem I feel, they would be saturated in one night. The moisture must be coming up from the wet soil and is being trapped within the hollow post as heavy condensation. The bollard post lights are similar to a mushroom design. There is no drying air flow internally. I am concerned about tracking and the corrosion of the electronics.

Bye,

Z.
 05 July 2014 10:01 AM
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Originally posted by: phantom9

That's a horrible topic heading. Yeuch!



Maybe this question should be directed at the bollard manufacturers. I can't see how this can be an installers problem unless the manufacturer's installation instructions have not been followed.


Mornin' phantom9,
I did not source the bollards and they were just thrown into a cardboard box by the supplying wholesaler and left with us. Paperwork? There was an instruction sheet, but no mention of condensation problems. No manufacturer's address or contact details. I am not the main contractor in this case. The light head could do with some external under mushroom head drainage holes I reckon to aid ventilation. But I am not going to drill any and invalidate any guarantee or destroy the anti-corrosion coating on the metal. AAAAAAAAAAAAAAAAhhhhhhhhhhhhhh we try out best.

Bye,

Z.
 05 July 2014 10:35 AM
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DOUGIE1000

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dont think this will help however I have used these years ago http://uk.rs-online.com/web/p/...osure-heaters/0500112/


data sheet http://docs-europe.electrocomponents.com/webdocs/0d7c/0900766b80d7c3fa.pdf

-------------------------
Dougie
Power Plus Electrical.co.uk

My mission is to live as long as possible......so far so good!
 06 July 2014 11:22 PM
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mapj1

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Is the pcb conformalyl coated (like varnish), and do they expect the cable entry to be sealed by spray-foam or similar.
Gel is at best a short term thing - in my experience it may slow down water damage, but it does not stop leaks !!
Photograph it and contact your supplier - you need them to realise that as supplied it is not fit for purpose.
In things with antennas out side, we either normally either
1) have holes high and low to get convection chimney effect going, (with fibreglass plug or submersion breathers to discourage insects )
or
2)an fully open lower skirt if its very short
or
3) If we must, we make it utterly hermetic to survive immersion to at least a metre. (as temperature variation cycles the pressure in a closed box, and if you don't make it at least this good then water or damp air gets blown and sucked past the seals over time)
There are sadly no long term successful half measures, ad attempts to make things that 'only leak a bit' end in bitter dissapointment..

Conformal coating ('con-coat') helps save PCBs from flashover and burns.

-------------------------
regards Mike
 07 July 2014 09:08 AM
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impvan

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Is this not just moisture released by the fresh concrete drying out? Just leave the doors off the posts as often as you can.

If you still get moisture penetration even when the concrete has dried (e.g. after heavy rain) then get 'tanking slurry' from a builders' merchant and pour a cup of it into the bottom of the post - this will seal the top of the concrete.
 07 July 2014 09:36 AM
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Hello and thanks all, especially mapj1 and impvan,
the posts have no access door at all. Access by removing the head only. The new heads were fitted on a hot day after the concrete had had many dry days to set and dry out. So we shall see what happens in the future.

Bye,

Z.
 07 July 2014 01:30 PM
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Ricicle

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Are the bollards up and running yet? I have this problem at work with bollards that have failed but generally the ones that work have no condensation as the operational heat keeps it at bay.

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 07 July 2014 03:16 PM
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mapj1

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Who makes them - are they aware of the effect, would a few photos and some words like 'poor design', 'inadequate' and 'money back' get a response I wonder?

The UK is not the wettest part of the world after all, and its not as if outdoor mains is a new idea.

-------------------------
regards Mike
 07 July 2014 05:39 PM
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sparkingchip

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The led bollards in Worcester on the river bank work completely submerged when the Severn is in flood creating a very artistic display, I don't think a bit of condensation will affect them!
 09 July 2014 11:09 PM
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DOUGIE1000

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Any reply or outcome?

-------------------------
Dougie
Power Plus Electrical.co.uk

My mission is to live as long as possible......so far so good!
 13 July 2014 06:51 PM
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Originally posted by: DOUGIE1000

Any reply or outcome?


Hello Doughie,
no real news to post. I have left that place of work now, it was only a short term contract. The bollards were all up and running when I left. Any future problems are now in the hands of the permanent maintenance team.

Bye,

Z.
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